As Humans Age, Their Connective Tissue, Rich in Collagen, Becomes

Multiple Choice

As humans age, their connective tissue, rich in collagen, becomes more rigid and brittle. What is the molecular cause of this change?

A) Collagen fibrils change their degree of supercoiling over time.
B) Many older adults have vitamin C deficiencies that result in collagen oxidation.
C) As cells age, a variant of collagen is expressed.
D) Crosslinks between collagen fibrils accumulate over time.
E) UV damage to collagen accumulates over time.