The correct option is
D Both (a) and (b)
At
16 weeks of pregnancy, the fetus shows the presence of fingers and toenails.
Even some facial features become distinct at this stage. The fetus weighs
around 3.5 ounces and is almost the size of an avocado, around 4.6 inches in height.So, the correct answer is 'Both (a) and (b)'.