Spring Tides occur:

Options

A. at new moon and first quarter moon
B. at first quarter and third quarter moons
C. at new moon and full moon
D. at third quarter and full moons

Explanation

### Step-by-Step Solution:

1. **Understanding Spring Tides**: Spring tides are a type of tide that occurs when the gravitational forces of the Moon and the Sun align with the Earth. This results in higher high tides and lower low tides.

2. **Position of the Moon and the Sun**: Spring tides occur during two specific phases of the Moon: the New Moon and the Full Moon. During these phases, the Earth is positioned between the Moon and the Sun (Full Moon) or the Moon is between the Earth and the Sun (New Moon).

3. **Frequency of Spring Tides**: Spring tides occur twice each lunar month, which means they happen approximately every two weeks. This is consistent throughout the year and does not depend on the seasons.

4. **Understanding the Timing**: After a Spring tide, approximately 7 days later, the Sun and the Moon are at right angles to each other, leading to lower tidal ranges known as neap tides.

5. **Conclusion**: Therefore, the correct answer to the question "Spring Tides occur:" is at New Moon and Full Moon.