Part III Vocabulary (20 minutes)
Directions: There are 30 incomplete sentences in this part. For each sentence there are four choices marked (A), (B), (C) and (D). Choose the ONE answer that best completes the sentence. Then mark the corresponding letter on the Answer Sheet with a single line through the centre. 【題組】50. At present, it is not possible to confirm or to refute the suggestion that there is a causal relationship between the amount of fat we eat and the _____ of heart attacks.
(A) incidence (C) rupture
(B) impetus (D) emergence