Answer:
The correct answer is option a.
Step-by-step explanation:
According to the law of demand, the price of a commodity and its quantity demanded are inversely related. So they change in opposite directions. As the price o a commodity decreases, it becomes cheaper. The purchasing power of the consumer increases and he is able to afford more of the product.
A decrease in the price of spaghetti will make it cheaper. People will be able to afford more spaghetti. As a result, the quantity demanded of spaghetti will increase. This will be indicated by a rightward movement on the same demand curve.