Mars Hardware Sold 20 Drills for $8 Each $\begin{array}{lrr} \text { Cash } &160\\ \text {Sales } &&160\\\end{array}$

Mars Hardware sold 20 drills for $8 each. Each drill cost $4. Which journal entry completely records the sale under a perpetual inventory system?
a.
$\begin{array}{lrr} \text { Cash } &160\\ \text {Sales } &&160\\\end{array}$

b.
$\begin{array}{lrr} \text { Cash} &160,\\ \text { Inventory} &&160\\\end{array}$

c.
$\begin{array}{lrr} \text { Cash } &160\\ \text { Cost of Goods Sold} &80\\ \text {Sales } &&160\\ \text { Inventory } &&80\\\end{array}$

d.
$\begin{array}{lrr} \text { Cash } &160\\ \text {Inventory } &&80\\\text {Gain from Sale}&&80\\\end{array}$