Multiple choice general knowledge adj. exhausting aspiration gruelling crabbed whet Reveal answer Fill a bubble to check yourself B Correct answer Explanation 'Gruelling' describes something that is extremely tiring and demanding, such as a gruelling workout or a gruelling journey. 'Aspiration' refers to ambition, 'crabbed' means difficult to read or surly, and 'whet' means to sharpen or stimulate.