Which of the following are surds ?
(a) `sqrt(9) " "(b)root(3)(13)" "(c)root(4)(25)" "(d)root(6)(32)`

Explanation

To determine which of the given options are surds, we need to analyze each option one by one. A surd is an expression containing a root that cannot be simplified to remove the root.

### Step-by-Step Solution:

1. **Option (a): \( \sqrt{9} \)**
- The square root of 9 is \( 3 \) (since \( 3^2 = 9 \)).
- Since we can simplify \( \sqrt{9} \) to \( 3 \), it is **not** a surd.

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