My brother -in-laws (a)/ who live in Mumbai have come (b)/ to stay with us .(c)/ No error (d)

In the following questions, some part of a sentence may have errors. Find out which part of the sentence has an error and select the appropriate option. If a sentence is free from error, select 'No error'. My sister-in -laws (1) // who live in Kolkata (2) // have come to stay with us. (3) // No Error (4)