Assertion–Reason (Tides):\nAssertion (A): Tides indicate the regular, periodic rise and fall of sea level.\nReason (R): Tides are caused by the gravitational pull of the Moon and sea level.

Introduction / Context:
The item checks understanding of what tides are and their primary causes. It also probes careful reading because the Reason statement contains a subtle error in phrasing.

Given Data / Assumptions:

• Assertion: Tides are regular periodic oscillations of sea level.
• Reason: Tides are caused by gravitational pull of the Moon and “sea level” (as written).

Concept / Approach:
Tides are generated mainly by the differential (tidal) gravitational forces of the Moon and the Sun acting on Earth’s oceans, modulated by Earth’s rotation and basin geometry. The Reason as stated improperly lists “sea level” instead of the Sun as a cause.

Step-by-Step Solution:
1) A: Correct. Tides are periodic rises and falls of ocean levels.2) R: Incorrect as written. The correct causal agents are the Moon and the Sun (plus Earth–Moon system rotation), not “sea level.” Therefore R is false.3) Relation: Since A is true and R is false, option indicating “A true, R false” follows.

Verification / Alternative check:
If the Reason had said “Moon and the Sun,” it would be true and would explain A. The provided wording invalidates it.

Why Other Options Are Wrong:
Any option treating R as true ignores the explicit wording error; saying A is false contradicts standard definitions.

Common Pitfalls:
Skimming past the misprint and assuming the standard correct text.

Final Answer:
A is true but R is false.