The correct answer is option 1, which includes statements 1 and 4.

Statement 1 is correct because if the price of a substitute good increases, the demand for the original good may increase as consumers look for cheaper alternatives.

Statement 4 is also correct as, in general, if the price of a good falls, more people are likely to buy it which results in an increase in market demand.

On the other hand, statement 2 is incorrect as if the price of a complement good increases, the demand for the original good might decrease. Complement goods are those that are typically used together - for example, bread and butter. So if the price of butter increases, people may decide to buy less bread.

Statement 3 is also incorrect. Inferior goods are those goods where demand decreases as consumer income increases. For example, people might buy less ramen noodles as their income increases because they can afford a more expensive substitute. So if the good is an inferior good and consumer income increases, the market demand for the good might decrease, not increase.