which element provides strength to the exoskeletons of clams and oysters?\no sulfur\no oxygen\no hydrogen\no…

Brief Explanations:

The exoskeletons of clams and oysters are mainly made of calcium - carbonate. Oxygen is a key element in the carbonate part of calcium - carbonate, contributing to the structure and strength of the exoskeleton. Sulfur, hydrogen, and phosphorus are not the main elements providing strength to their exoskeletons.

Answer:

oxygen