What Does the Term Conditionally Indispensable Mean

What does the term conditionally indispensable mean?

A) Under stressful conditions, amino acids that normally could be made by the body must be provided by the diet.
B) Under certain conditions, the body only needs 10 amino acids not the usual 20 amino acids to build and repair tissue.
C) Under no conditions can these amino acids be broken down to provide energy.
D) Under starvation conditions, these amino acids can be manufactured without a nitrogen-containing (amino) group.