Both Your son __________ daughter are tall.

Both Your son __________ daughter are tall.

Explanation

Both Your son and daughter are tall. آپ کا بیٹا اور بیٹی دونوں لمبے ہیں۔

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"And" conjunction is used for joining two words, phrases, or clauses
In the above sentence "Son and daughter" are joining" for the discussion of his/her tall" so we chose the option "AND"
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Generally, the correlative Adverb Both is followed by And. 

Whether is followed Or.

Neither is followed by Nor.
ND05-12-2022