Directions: Read the given sentence to find out whether there is any grammatical error or idiomatic error in it. The error, if any, will be in one part of the sentence. The number of that part is the answer. If there is no error, the answer is (5). (Ignore errors of punctuation, if any).

These recently upgraded branch offices (1)/ have been fully computerised (2)/ and are connected to headquarters (3)/ to ensure proper monitoring. (4) / No error (5).

The error is in part (3): 'are connected to headquarters'. After 'have been fully computerised', the logical connector should be 'and' (coordinating conjunction), not 'to'. The sentence should read 'have been fully computerised and connected to headquarters'. Part (3) 'to ensure proper monitoring' is correct. Actually, re-reading carefully: The structure is 'have been fully computerised and are connected to headquarters' - this is correct. Wait, let me re-examine... Actually, the error is in part (3) - it should be 'and are connected' not just 'are connected' to maintain parallel structure with 'have been computerised'.