The correct option is A Bitter in taste
Baking soda will create leavening on its own when it is heated, On heating, it is converted into sodium carbonate which is bitter to taste but unless it is balanced with an acidic ingredient, the resulting taste may be metallic.
Baking soda is a base, and these have bitter tastes. If they're not carefully mixed in with an acid that can neutralize them, they result in bitter food.
Thus, If at home your mother uses baking soda instead of baking powder in cake, the taste will be little bitter.