I need help with this question please

Question 5 (1 point) Amount Security (in Billions) Treasury Bills $220 Corporate Bonds 140 Treasury Notes 80 Corporate Stock 200 US Savings Bonds 60 Treasury Bonds 100 Other things equal, an increase of corporate bonds from $140 billion to $150 billion in the economy would: ( 1) not change the size of the public debt. ( 2) increase the public debt from $460 billion to $470 billion. ( 3) increase the public debt from $600 billion to $610 billion. ( 4) decrease the public debt by $20 billion