Assertion. Actinoids show larger number of oxidation states than lanthanoids.
Reason. Highest oxidation state showsn by lanthanoids is `+4` while that of actinoids is `+7`

Explanation

To analyze the assertion and reason provided in the question, we can break down the information step by step.

### Step 1: Understanding the Assertion
The assertion states that actinoids show a larger number of oxidation states than lanthanoids.

**Explanation:**
- Actinoids (elements 89-103) are known to exhibit a variety of oxidation states ranging from +3 to +7.
- In contrast, lanthanoids (elements 57-71) primarily exhibit oxidation states of +3, with +4 being the highest oxidation state observed in some cases.
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