Tardigrades can survive decades without water by entering a state called cryptobiosis.
Why it is true
When water is scarce, the tardigrade curls into a dry ball called a tun. In this state, its metabolism slows dramatically and it can withstand extreme temperatures, radiation and pressure until conditions improve.
Source: Nature
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.