1. Genes are __ x Segments of DNA that carry the instructions for the traits of an organism from parents to offspring (B) Located on chromosomes in the nucleus of a cell c The basic units of heredity All of the above 2.

# Explanation:<br />## Step 1<br />The problem presents a multiple-choice question about the nature of genes. The options are:<br />A. Segments of DNA that carry the instructions for the traits of an organism from parents to offspring<br />B. Located on chromosomes in the nucleus of a cell<br />C. The basic units of heredity<br />D. All of the above<br /><br />## Step 2<br />Each of the options A, B, and C provides a correct description of genes. <br /><br />## Step 3<br />Option A describes genes as segments of DNA that carry the instructions for the traits of an organism from parents to offspring. This is a correct description of genes.<br /><br />## Step 4<br />Option B describes genes as located on chromosomes in the nucleus of a cell. This is also a correct description of genes.<br /><br />## Step 5<br />Option C describes genes as the basic units of heredity. This is another correct description of genes.<br /><br />## Step 6<br />Since all the options A, B, and C are correct descriptions of genes, the correct answer is D, which states "All of the above".<br /><br /># Answer: <br />