(31) The rough endoplasmic reticulum (A) has ribosomes bound to it (B) is part of the membrane system found throughout the cell's cytoplasm (C) is connected to the nuclear envelope (D) all of the above

(D) all of the above

Explanation:

The rough endoplasmic reticulum is part of the endoplasmic reticulum, the other one is known as the smoother endoplasmic reticulum.

1. This rough endoplasmic reticulum is considered rough because it has ribosomes bound to it.

2. Also, it is part of the membrane system found throughout the cell's cytoplasm, even though its density is considered to be higher in some places, such as near the nucleus.

3. It is also is connected to the nuclear envelope or membrane

Some of its functions include

1. It produces antibody in certain leukocytes

2. It produces insulin in pancreatic cells

Hence, in this case, the correct answer is Option D "all of the above."