Algebra-1

Question Analysis
This question tests the student's ability to identify and calculate the common ratio in a geometric sequence, specifically one with alternating signs. The sequence provided is simple and straightforward, making it suitable for an easy-level question.

Key Concept Explanation
The common ratio in a geometric sequence is the ratio of each term (starting from the second term) to its preceding term. It is a fixed constant for the entire sequence, even if the terms alternate in sign.

Step-by-step Solution
1. Identify the first two terms of the sequence: and .
2. Calculate the common ratio using the formula