<span>The research shows that the relationship between estrogen and verbal tasks is negative while it is positively correlated with spatial tasks. This correlation shows that, like in other animal studies, there could be some sort of organizing of the brain that goes on related to the level of sex hormones in the body.</span>
The true answer of your question is :
OH : HYDROXYL GROUP
NH2 : AMINO GROUP
CH3 : METHYL GROUP ( but in rather broader terms, that functional group of formula CnH2n+1 where n is an integer is called ALKYL GROUP where by substituting n by 1,2,3... we obtain methyl for n = 1, ethyl for n = 2, and propyl for n = 3 )
COOH : CARBOXYL GROUP is the correct answer since carbonyl is characterized by the presence of functional group C=O in general the formula of the compound would be
R-C=O-R’ where R and R’ are alkyl groups like methyl for example. However the carboxyl group could be thought of as a summation of carbonyl + hydroxyl ( CO + OH ) resulting thus in COOH.
I hope you’ll understand everything, anyway if not i’m always here to help. ♥️