hi aspirant ,

All three are best field . It depends on your interest . If you are interested in working in companies like amazon , flipkart , swiggy , zomato then data science is good and if you want to go for companies like google  for product development then ML AND AI is best . Actually these courses are 3 stages of modern computer science it start from data science then machine learning and then artificial intelligence . artificial intelligence can do both ml and data science .