What is the semantic method for marking up a video with a caption in browsers that support it?
<video src="video.mp4"><caption default srclang="en" src="video.vtt" /></video> Source
<video src="video.mp4"><caption default srclang="en" src="video.vtt" /></video>
<video src="video.mp4" caption="video.vtt"></video>
<video src="video.mp4"><track caption="video.vtt" /></video>
<video src="video.mp4"><track default kind="captions" srclang="en" src="video.vtt" /></video>