Checking the four statements one by one: ozone really is bent, because of the lone pair on the central oxygen; solid ozone really is violet-black; ozone really is diamagnetic, with all its electrons paired; and ONCl and ONOX− really are not isoelectronic, since they carry different electron counts. Every statement is in fact correct, so there is no genuinely wrong option, and the item was treated as a bonus with full credit.
JEE Main · 2013 · 07 Apr 2013 · Offline · Single correct option