What will be the output of the following R code?

> m <- matrix(1:4, nrow = 2, ncol = 2)
> dimnames(m) <- list(c("a", "b"), c("c", "d"))
> m

A. <- B. = C. -> D. assign()

A. Display the result of a calculation B. Read input from the user C. Plot a graph D. Install a package

A. set B. = C. -> D. assign()

A. Create a sequence of numbers B. Sort a vector C. Merge two data frames D. Compute the mean of a numeric vector