Choice "A" is correct. The common disadvantage of all capital budgeting models is their reliance on future data. Capital financing relates to longer periods of time that are subject to greater levels of uncertainty than other short-term budgeting and financing decisions.
Choice "c" is incorrect. While the failure to consider the time value of money is a shortcoming of the payback method, it is not a common weakness in NPV and IRR methods or other discounted cash flow methods that do consider the time value of money.
Choice "d" is incorrect. While the IRR method may require multiple trial-and-error computations, other methods do not. This weakness is not common to all of the capital budgeting methods mentioned.
Choice "b" is incorrect. The cost of capital is a typical hurdle rate used in discounting future cash flows in capital budgeting, but it is not used for the payback method. Cost of capital considerations are not common to all of the capital budgeting methods mentioned.