Which cellular environments is conducive to the formation of disulfide bonds within or between proteins?

The rough ER

Explanation:

Generally the formation of native  disulphide bond is essential for the folding and maturation of  proteins in the secretory pathways.These bonds are formed in the rough E.R, and also in the intramembrane of the mitochondria.

Basically an oxdative parthways is required  for the disulfide bond to form, while a reductive pathway is needed for the formation of isomers for non-native disulphide bonds. These oxidative pathways takes place in the rE.R

Generally the disulphide bonds is usually formed by oxidation of  two cysteines bonds. it does not occur in the cytoplasm because it is always in reduced state due to the presence of disulphide reductase. The same explains why it does not occur in the Nuclei

some fungi obtain their nutrients from a living host (plant or animal) and are called most biotrophic fungi have fairly narrow host ranges—they are specialized on a limited called rhizomorphs that allow the fungus to grow from one tree to another. ascospores are formed inside a sac-like structure called an ascus. so your answer is a