___________ is a measure of a person's intellectual development relative to people of her/his age group.

Mental Age

The correct answer is option 2: Mental Age

Mental Age (MA): This concept was introduced by the French psychologist Alfred Binet. It is a measure of a person's intellectual development relative to their peers. For instance, if a 10-year-old child performs tasks on an intelligence test typical of an average 12-year-old, their mental age is considered to be 12.

Why Other Options Are Incorrect

• Option 1: Chronological Age (CA): This is simply the actual biological age of a person from their date of birth (e.g., being 15 years old). It does not measure intellectual capability or development.

• Option 3: Emotional Intelligence (EI): This refers to a person's capacity to recognize, understand, manage, and reason with emotions. It is distinct from cognitive or intellectual development benchmarks.

• Option 4: Intelligence Quotient (IQ): While closely related, IQ is the final numerical score derived from a formula that compares mental age to chronological age. Therefore, IQ is a numerical score calculated using Mental Age and Chronological Age, whereas the specific measure of intellectual development relative to the age group is Mental Age.

NCERT: "In 1905, Alfred Binet and Theodore Simon, made the first successful attempt to formally measure intelligence. In 1908, when the scale was revised, they gave the concept of Mental Age (MA), which is a measure of a person’s intellectual development relative to people of her/his age group. A mental age of 5 means that a child’s performance on an intelligence test equals the average performance level of a group of 5-year olds. Chronological Age (CA) is the biological age from birth. A bright child’s MA is more than her/his CA; for a dull child, MA is below the CA. Retardation was defined by Binet and Simon as being two mental age years below the chronological age."