The table shows four transactions involving the United Kingdom.
| Letter | Transaction |
|---|---|
| A | An overseas family pays for rooms in a hotel in Wales. |
| B | A UK supermarket buys bananas grown abroad. |
| C | An overseas company pays a UK insurer for insurance cover. |
| D | A UK manufacturer sells bicycles to shops abroad. |
Give the letter of one transaction that is a UK export of a service.