Why can't capital accumulation alone lead to sustained economic growth?

Select one:

a.

Many firms do not use capital so accumulating capital will not have any impact on growth

b.

Accumulating capital costs money. This expenditure limits the amount of economic growth the economy can experience

c.

Eventually the economy will begin to experience diminishing marginal product of capital

d.

Any increase in the amount of capital needs to be met with an increase in the amount of labour so increasing capital alone cannot lead to sustained growth