Select all sentences with both correct inversion and the standard connector pairing.
Hardly the meeting had ended when the lights failed.
Hardly had the meeting ended when the lights failed.✓Correct answer
Scarcely had the van departed when the call came.✓Correct answer
No sooner had the van departed than the call came.✓Correct answer
Explanation
The acceptable sequences use past-perfect inversion and keep hardly or scarcely with when and no sooner with than. The rejected sequence uses statement order after a fronted restrictive adverb.