While visiting an exhibit on seventeenth-century life, rachel noticed that the adult clothing and shoes seemed to be quite small. the curator explained that current generations are taller than past generations, a phenomenon known as
(a) the secular trend(b) obesity(c) genetic predisposition(d) more exercise

The correct answer is - option A) the secular trend.

Explanation:

The secular trend is the constituent of the time period that provides the general tendency of the particular data for a long time of a period. It is the phenomenon.  

The growth of the population in a particular area over a period of time is a good example of a secular trend. In the given question trend is moving with every generation by generation and become taller.

Thus, the correct answer is - option A) the secular trend.