Choose the most appropriate adjective.
Of all the workers in the shop, Jerzy is surely ______________

the least competent

The correct adjective to use in the blank is the least competent. The word least is the superlative form of the adjective little, which means that it indicates the smallest degree of something. In this case, of all the workers in the shop, Jerzy is surely the least competent, which means that he is the least skilled or capable of the workers.

The other options are incorrect.

• The less competent is the comparative form of the adjective little, but it would not be appropriate in this context, as it does not indicate the smallest degree of competence.
• The competentest is not a word in the English language.
• None of the above is not an adjective.