Which of the following should be set on chunk by chunk basis to store results of computation?

The correct answer is: A. cache=TRUE

The cache argument is used to specify whether or not to store the results of computation. If cache=TRUE, then the results of each chunk will be stored in memory. This can speed up subsequent computations, as the results of previous chunks will not need to be recomputed. However, it can also use more memory, so it is important to use this option judiciously.

The cache=FALSE argument specifies

that the results of computation should not be stored in memory. This can save memory, but it can also slow down subsequent computations, as the results of previous chunks will need to be recomputed.

The caching=TRUE argument is a deprecated option that is equivalent to cache=TRUE. It is not recommended to use this option, as it will be removed in a future version of R.

The none of the mentioned option is incorrect, as it does not specify whether or not to store the results of computation.