Both. It depends if you're talking in present tense, like you're sitting there, watching Jim playing, or if you're referring to something that happen a while ago and you're not there. In the case of present tense, 'scored' would be right. Past tense would be 'had scored.' This sentence leans a bit to the past tense, so it would sound best as 'had scored,' although I wouldn't personally do that, because it seems proper. Scored works too, but I believe the grammatically correct one for past tense would be 'had scored.'

I think A is right.如果是考试的话，他想考察的是过去完成时。

Thanks! @Gertie!

I feel like either could work but B is better. Just simple preterite.