Which of the following ‘suffixes’ used for units of classification in plants indicates a taxonomic category of ‘family’?
1.   — Ales

2.   - Onae

3.  — Aceae

4.   - Ae

(c) The name of a family, a taxon, in plants always end with suffixes aceae, e.g., Solanaceae, Cannaceae and Poaceae
Ales suffix is used for taxon ‘order’ while ae suffix is used for taxon ‘class’ and onae suffixes are not used atall in any of the taxons.