(C) Assertion (A) is true, but Reason (R) is false.
A child bears all basic human features, but it does not look exactly like its parents — human populations show a great deal of variation.
The textbook (Chapter 8, Section 8.2.1) explicitly states: "a child bears all the basic features of a human being. However, it does not look exactly like its parents, and human populations show a great deal of variation." So A is correct, but R contradicts the textbook — making R false. Option (C) is the only fit.