Соотнесите предложение на русском языке с английским вариантом перевода. После того как прибор тщательно проверили, его запустили в действие.

The device was carefully put into operation before testing.
Having been carefully tested the device was put into operation.
The device was carefully tested before sending it into operation.

Having been carefully tested the device was put into operation.

Объяснение:

1. The device was carefully put into operation before testing. — После того, как прибор тщательно запустили в действие, его проверили.

3. The device was carefully tested before sending it into operation. — После того как прибор тщательно проверили, его отправили в действие.