During conception when there are 47 chromosomes instead of the normal 46, it leads to:

Correct option is A

Mental Retardation / Intellectual disability is the correct answer. When there is an occurrence of 47 chromosomes in a human, instead of the normal 46, it often results in chromosomal disorders that can lead to various developmental and intellectual disabilities. The most common example of this condition is Down syndrome, which is typically caused by an extra copy of chromosome 21 (trisomy 21). This additional chromosome leads to intellectual disability and may also be accompanied by physical abnormalities and developmental delays.
While individuals with chromosomal abnormalities like trisomy 21 may experience a wide range of physical impairments, the most prominent and universally recognized outcome of having an extra chromosome in many cases is intellectual disability. This encompasses challenges in cognitive functioning, learning abilities, and adaptive behaviors. Other physical, hearing, or visual impairments may also occur, but intellectual disability is the primary and most significant manifestation associated with this genetic condition.