Answer:
b) Debt Investments: 520,000 | Interest Revenue: 12,500 | Cash: 532,500 
Step-by-step explanation:
The journal entry to record the purchase of the bond is shown below:
Debt investment Dr $500,000 × 1.04) $520,000
Interest revenue Dr ($500,000 × 10% × 3 ÷ 12) $12,500
 To Cash $532,500
(being the purchase of the bond is recorded)
Here the debt investment and interest revenue is debited as it increase the assets and decreased the revenue while on the other hand the cash is credited as it decreased the assets 
Hence, the correct option is b.