The correct answer is Science of Experience. E.B. Titchener (1867–1927) formally defined psychology as the science of experience to distinguish it from other sciences and to establish its domain as the study of conscious processes as they are experienced by the individual.

Context & Definition

• Founder of Structuralism: Titchener founded Structuralism, which was the first formal school of psychology in the United States. He believed that the primary goal of psychology was to discover the basic "atoms" of the mind.
• The Definition in Detail: He argued that psychology should study the structure of the human mind by analyzing the basic elements of immediate, conscious experience. For Titchener, psychology was not about the physical world itself, but about the experience of that world. He famously asserted that physics studies experience independent of the perceiver (e.g., a chair as a physical object), whereas psychology studies experience as it is dependent on the experiencing person (e.g., the perception and sensation of the chair).
• The Method – Introspection: To study this structure, he employed introspection—a rigorous, trained method of self‑observation. Trained participants would report their conscious experiences (breaking them down into sensations, images, and feelings) in response to controlled stimuli, allowing Titchener to map the basic elements of consciousness.

Why the Other Options Are Incorrect

• Science of Soul (Option 1): This definition belongs to ancient and medieval philosophy (e.g., Plato, Aristotle, and early religious scholars). Titchener explicitly rejected metaphysical concepts like the "soul," insisting that psychology must be an empirical, natural science grounded in observable experience.
• Science of Mind (Option 2): While this is a common, general definition of psychology (used by figures like William James), it is too broad for Titchener’s strict operationalism. He specifically narrowed the focus to experience to avoid mentalistic speculation that could not be directly observed or experimentally measured.
• Conscious Experience (Option 4): This phrase accurately describes the subject matter that Titchener investigated (since he focused on the conscious mind). However, his formal, explicit definition of psychology as a science was "Science of Experience." He used this precise wording to differentiate his structuralist program from physics and biology. While "Conscious Experience" is closely related, the exact textbook answer to this specific MCQ is "Science of Experience."

In summary: Titchener redefined psychology to make it an experimental science of the conscious mind, breaking it down via introspection. His official definition—Science of Experience—remains the definitive answer to this question, clearly separating psychology from philosophy and the physical sciences.

The correct answer is Early childhood because this developmental stage is famously characterized by a child's rapid language acquisition and an intense curiosity about how the world works, leading them to constantly ask 'why?'

• Step 1 (Fact Check): Your original prompt listed Puberty as the correct answer. Developmental psychology notes that the 'Why' age specifically refers to Early Childhood (typically ages 2 to 6). During this period of growth, a child's brain is rapidly developing, and they utilize question-asking as a primary mechanism to construct mental frameworks and process information. The correct field has been updated to reflect accurate developmental science.
• Step 2 (Psychological Significance): Asking 'why' continuously during early childhood marks the transition into Piaget's preoperational stage of cognitive development. It demonstrates that the child is moving away from purely sensorimotor interactions and is actively trying to grasp cause-and-effect relationships.
• Incorrect Options:
  • Late childhood is incorrect because children at this stage (ages 6 to puberty) move past basic curiosity questions and focus more on social peer relationships, industry, and mastering logical operations.
  • Puberty is incorrect because it is marked by intense physiological changes, sexual maturation, and emotional transitions, rather than the initial language-based 'why' questioning phase.
  • Late adolescence is incorrect because this final stage before adulthood focuses heavily on identity formation, abstract future planning, and establishing personal values.

The first experimental psychology laboratory was established in Frankfurt, marking a pivotal moment in the scientific study of the mind.

Intelligence tests, emerging in the late 19th century, were among the earliest systematic and standardized psychological methods developed to quantify individual differences in cognitive behavior.

John Locke proposed the influential concept of "tabula rasa," or "blank slate," suggesting individuals acquire knowledge solely through experience.

John B. Watson, a key figure in behaviorism, asserted that behavior is primarily shaped by environmental factors such as reinforcement and punishment.