There's nothing to doubt还是there's nothing to doubt about

There's nothing to doubt还是there's nothing to doubt about
There's nothing to doubt还是there's nothing to doubt about

There's nothing to doubt还是there's nothing to doubt about
我认为加about,虽然doubt既是及物动词也是非及物动词,但在这个句子中加about有种不要随便怀疑的意思,.
仅供参考

doubt是及物动词，所以不需要接about
所以应该是
There's nothing to doubt.