Final answer:
Mental age is a method of estimating a child's intellectual ability by comparing their performance on intelligence tests with the average performance of children at a certain chronological age. It is a key component of calculating IQ, which is useful in various settings, although the validity of IQ tests is still debated.
Step-by-step explanation:
Mental age can best be defined as (A) A method of estimating a child's intellectual ability by comparing the child's score on intelligence tests and his or her age. This concept is used to express a person's intellectual capacity in terms of the age at which an average individual reaches the same level of performance on an IQ test. For instance, if a 10-year-old child has a mental age of 8 based on their test scores, this means they perform on the intelligence test similarly to the average 8-year-old.
The mental age concept is intrinsic to the computation of the Intelligence Quotient (IQ), which is then used to measure intellectual ability. By comparing an individual's mental age to their chronological age, a ratio is established, which is multiplied by 100 to give the IQ score. This measurement can play a crucial role in educational and clinical settings for identifying individuals who may require additional support.
It is important to recognize that discussions surrounding the validity of intelligence tests, what they should assess, and the implications of their results, continue to be points of debate among researchers and practitioners in the field of psychology.