Explanation:
To find the sum of the terms in an arithmetic sequence, use the formula for the sum of an arithmetic sequence:

\[
S_n = \frac{n}{2} \times (a_1 + a_n)
\]

where:
- \( n \) is the number of terms,
- \( a_1 \) is the first term,
- \( a_n \) is the last term,
- \( S_n \) is the sum of the terms.

Given:
- \( n = 25 \),
- \( a_1 = 60 \),
- \( a_{25} = -12 \).

Step-by-Step Calculation:

1. Substitute the values into the sum formula:

\[
S_{25} = \frac{25}{2} \times (60 + (-12))
\]

2. Calculate inside the parentheses:

\[
60 + (-12) = 48
\]

3. Substitute and simplify:

\[
S_{25} = \frac{25}{2} \times 48
\]
\[
S_{25} = 25 \times 24 = 600
\]


The sum of the terms of the sequence is 600.

The correct answer is A. 600.