What two programming language deficiencies were discovered as a result of the research in software development in the 1970s?

Absence of type checking Absence of control statements

Explanation:

In the research of software development in 1970 it is found that there are two deficiencies.

1 Absence of type checking

The researcher sees that there is a fault in the type checker we can not convert one datatype into the other data type also it gives error in converting the one datatype into another.

2 Absence of control statements

The control statement plays an important role in the programming language. When the condition of the multiple arises then in that condition we used the control statement. in 1970 their is deficiencies of control statement.

Hence type checking and control statements are the two programming language deficiencies which are found by the researcher in software development of 1970.