Which activity is the example of an ideal workout for cardiovascular health?

an hour of quick walking

45 minutes of yoga

30 minutes of intense strength training

25 minutes of intense interval training

Yoga and strength training are both anaerobic, I believe.
An hour of quick walking would undoubtedly work the cardiovascular system, but an hour seems intense.
Twenty-five minutes of intense interval training would be ideal, as the intensive exercise is interspersed with less intense rest exercises. It has also been shown that this type of training is more efficient than training at a steady level for a longer period (for example, an hour of quick walking).

It allows water to resist freezing and thawing cycle.