Which of the following sentence is correct?

Any one of the statements could be true. World is not very logical.

This is a choose the best answer types, so i go with the choice B . Which says - " Increased Advertising spending leads to increase in sales -with just an add on for many products today-as they are media based .

B-Increased advertising spending leads to increased sales. (I believe you consider ATL along with BTL) than 'B' would be the right answer. 

Both A and B could be both True and False.  Therefore both C and D could both be True.

There is insufficient information to answer the question because there is no trending or historical data given.  Sales is a goal.  Advertising is an expense to achieve a goal.  If advertising spending was increased and then sales increased, then A would most likely be true.  If advertising was decreased or remained steady, and then sales increased, the increase would be attributed to something else and advertising spending would not be increased. Thus A is both true and false.  A similar argument can be made for sentence B.  

If one holds that to be true a statement must always be true, but a single negation causes the statement to be false, then logically, the only correct answer (or most correct answer) is D. 

b

c

It is True that Increased advertisement spending leads to increased sales

Normally, Every company works on proposal that more we spend on advertising more we can generate sales it all works on logical solution to promote your brand sales but doesn't come with fixed formulas like mathematics i.e.,1+1=2.

It is too hypothetical to say that increase your advertising expenditure and it will result in guaranteed incremental sale. 

B is correct answere in this case.

I totally agreed with Mr.Vinod's answer.