The minimum number of page frames that must be dedicated for a process is determined by Instruction set architecture.
Suppose that a instruction requires 4 pages to run till completion. Eg: it mat require 1 page for code segment, 2 pages for storing data operands and 1 page for storing stack segment. Now if we allocate only 3 pages that means only 3 pages will be present in the main memory at a time, say we didn't provide a page for stack. Then code has been executed, operand has been fetched but when we try to store the result we get a page fault. So when we get a page fault during execution the instruction has to be started again. So instruction set determines the minimum page frame.