Mass Communication

See these both are very different fields, one is for managing business administration, whereas, another is in media and journalism world. Both have got a very deep need in this world. One connects the world by imparting news around the globe, whereas, another connects to the world with there effective products and services to every part possible.
Nowadays, as media has diverse fields like radio, print media, TV, and others with much tough competition, where you need much art in your hands (Pen) and words. So, to go in this field, you need to have skills.
1. Writing power
2. Speaking art
3. Patience
4. Calmness
5. Great interest
It has a good scope if you have interest.
Whereas, in management also you have great and increasing demand as, nowadays, startups are increasing with requirements of skilled professional managers to take their business to great heights. For this, you need to have
1. Brain twisting (situational)
2. Communication skill
3. Patience
4. Risk taking heart
5. Cooperative nature
I will just suggest better than thinking too much, think that which course you got much interest in and from which you can achieve better scope.
Hope you got your answer.
All the best.

Screenwriting is a process of writing a script, but this is only used for filmmaking that has narrative elements that involve dramatic elements and other components of the film that need to be seen on the screen to serve the overall narrative like the setting, the lighting and movements. Screenwriting provides the visuals that complement what the characters are doing and saying. The mood accentuates the drama or humour that the characters are executing based on the script.
It deals more with how the story is going to be perceived by describing where the characters are, what they are doing, what they are saying and everything else that's happening around them. It may not even include character dialogues to accomplish this.