Select the correct indirect form of the given sentence.

She said to her friend, “Will you take my dog for a walk?”

She asked her friend if she would take her dog for a walk.

The correct indirect form of the given sentence is: She asked her friend if she would take her dog for a walk.

Explanation:
When changing a direct question into indirect speech, we typically use "asked" instead of "said," and we use "if" or "whether" to introduce the reported question. Additionally, the modal verb "will" changes to "would" in indirect speech.

So, the correct option is: "She asked her friend if she would take her dog for a walk."