- A leaf performs photosynthesis / gas exchange
- A leaf is a part of a plant
- Photosynthesis makes food for the plant by converting carbon dioxide, water, and sunlight into carbohydrates
- Hence, the leaf part of a plant makes food by photosynthesis

- The leaf part of a plant makes food by photosynthesis
- A pine tree is a kind of plant
- So, the leaf part of a pine tree makes food by photosynthesis

- A needle is a part of a pine tree
- A needle is the leaf of a pine tree
- Therefore, a needle is the leaf part of a pine tree

- The leaf part of a pine tree makes food by photosynthesis
- A needle is the leaf part of a pine tree
- Hence, the needle of a pine tree makes food for pine trees by photosynthesis

So, the needle of a pine tree makes food for pine trees by photosynthesis
Which part of a pine tree makes food?
- A pine tree is a kind of plant 
- A needle is a part of a pine tree 
- A needle is the leaf of a pine tree 
- A leaf performs photosynthesis / gas exchange 
- A leaf is a part of a plant 
- Photosynthesis makes food for the plant by converting carbon dioxide, water, and sunlight into carbohydrates