Answer:
To become a vet you will require high (or even top) grades in all your GCSE subjects as it is a very competitive field to enter with far more applicants than places available. In general Chemistry is the most important along with the other sciences (Biology and Physics). Mathematics and English are also key subjects.
The reason Chemistry is considered the most important subject is because the majority of veterinary courses require Chemistry at A-level as a pre-requisite. Others also specify Biology as a co-requisite. Any other one or two from the following list is also recommended: Biology, Physics and Maths.
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