$17-5.$ Products G and H are joint products developed from the same process with each being processed further. Joint costs are incurred until splitoff, the separable costs are incurred in further refining each product. Sales values of G and H at splitoff are used to allocate joint costs. If the sales value of G at splitoff increases and all other costs and selling prices remain unchanged, joint costs allocated to:

$$ G $$H $$

a$.$increases $$increases

b$.$increases $$decreases

c$.$decreases $$decreases

d$.$decreases $$increases