Final answer:
The question deals with source and target data in information systems. Statements (a) and (d) are not necessarily true, as source data can come from various types of accounts and transactions can have multiple lines of target data.
Step-by-step explanation:
The question regarding source and target data relates to data flow and management in information systems or computer science. When dealing with transactions and data movement in systems, several aspects need to be understood.
Statement (a) suggests that source account data must be a balance sheet account. However, source data can also come from income statements or other types of statements depending on the context. Therefore, this statement may not necessarily be true. Statement (b) that source data provides information about classes seems more relevant to programming and object-oriented models rather than financial data. Statement (c) implies transactions typically have one line of source data, which can be true in many transactional systems where a single line corresponds to one transaction entry. Finally, statement (d) suggests that transactions cannot have more than one line of target data. This is not true; transactions can have multiple lines of target data, representing multiple effects caused by a single transaction in different accounts or places.
Without more context, it's challenging to definitively say which statements are true, but generally speaking, transactions can have more complex structures than those described by the statements.