Mahatma Gandhi taught us (a)/ that one should respect (b)/ The religions of others as much as his own.(c)/ No error (d)

In the following question, some part of the 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'. Our professor taught us that (1)/ one should respect the (2)/ religions of others as much as his own. (3)/ No Error (4)