Select the correct option: If the security protocol ___ breached, the system alerts administrators instantly.
- (a)were
- (b)is
- (c)has
- (d)had been
Answer
Why
Correct — B. The trigger is the main clause, the system alerts administrators instantly. That is the present simple, describing what always happens when the condition is met: a zero conditional.
A zero conditional takes the present simple in the if-clause too. The protocol is what gets breached, so the verb is passive: is breached → option (b).
Why the others are wrong
- (a)were — were gives 'were breached', the hypothetical form of a second conditional. That pairs with would alert, not with the present-tense alerts the sentence prints.
- (c)has — has gives 'has breached', active voice, which makes the protocol the intruder. The protocol is what gets breached, so a passive is needed.
- (d)had been — had been gives the past perfect of a third conditional, which pairs with would have alerted. It clashes with the present-tense alerts.
Concept
Conditionals are matched by tense pairs. Read the clause you are given, then build the other half to match.
Zero: if + present simple, present simple, for rules and automatic results.
First: if + present simple, will + verb, for a likely future.
Second: if + past simple or were, would + verb, for an unreal present.
Third: if + past perfect, would have + past participle, for an unreal past.
Here the main clause prints alerts and instantly: a system rule, not a guess or a regret. That is the zero pattern.
The zero and first conditionals share the same if-clause. 'If the protocol is breached, the system will alert administrators' would also be correct. Either way the if-clause takes is.
Key facts
- Zero conditional: if + present simple, present simple, for rules and automatic results.
- Second conditional: if + past simple or were, would + base verb.
- Third conditional: if + past perfect, would have + past participle.
- A subject that receives the action takes the passive: the protocol is breached.
Study next
Common traps
- Reaching for were because it sounds formal, without checking that the main clause has no would
- Choosing has because breached looks like a finished action, and missing that the protocol cannot do the breaching
Here the tense of the main clause fixes the verb in the if-clause.
18 Sep 2025, 12:30, English Q.9 tests the third conditional in inverted form: 'Had they submitted the proposal earlier, they ___ the funding', keyed would have received.
Related PYQs
No directly related past PYQ was found.