How tough is it to score 70 in the IGNOU BA?

You must conduct conceptual research. You must write answers that are free of grammatical errors. If you look through previous year question papers, you will notice that IGNOU asks less traditional questions. IGNOU asks questions based on your concept, such as "what do you think," "what is your opinion," and so on. Everything is contained in the study materials. You simply must take both the assignment and the TEE seriously. 

Start preparing for each TEE one month in advance, and dedicate that one month solely to your BA degree. It is advised to watch videos and read articles from GOOGLE. Concentrate on conceptual research. It will be beneficial to achieve more than 65% overall. It would not be difficult to obtain a 70% in IGNOU. Just consistency is required.