Under the Negotiable Instruments Act, 1881:
A negotiable instrument must be in writing, signed by the maker or drawer, and must contain an unconditional promise or order to pay a certain amount of money. This statement is correct.
A promissory note can be transferred through endorsement and delivery, as well as by assignment. However, a bill of exchange can also be transferred through endorsement and delivery, not only by formal assignment. Therefore, this statement is incorrect.
The holder of a negotiable instrument can indeed sue the drawer, maker, or endorser of the instrument if it is dishonored. This statement is correct.