Final answer:
Segregation of duties (Option 1) is the most likely control to deter the lapping of collections as it prevents an individual from having control over both recording and handling cash, which effectively reduces the opportunity for such fraud to occur.
Step-by-step explanation:
The most effective internal control to deter the lapping of collections from customers is Option 1: Segregation of duties. Lapping is a fraudulent practice where a person delays the recording of cash receipts from one customer and covers it up with receipts from another customer. By segregating the duties, one individual is not responsible for both recording receivables and handling cash, thereby reducing the opportunity for an employee to commit this type of fraud.
Option 2: Independent reconciliation of accounts would be helpful as well, but it's often a detection control rather than preventative like segregation of duties is. Having oversight by a separate person who can compare the recorded transactions with the actual bank deposits can detect lapping but may not completely deter the initial act.
Option 3: A top-down approach to controls may establish a good control environment but does not specifically address the risk of lapping in cash collections, while Option 4: Increased employee training can make employees more aware of the company's controls and ethics policies but doesn't provide a structural barrier against lapping.