Statements:
1. Some drip irrigation systems are automated.
2. All automated systems require electronic sensors.
3. No sensor-operated device is completely maintenance-free.
Which of the following conclusions logically follows beyond doubt?
Options:
(A) All drip irrigation systems require electronic sensors.
(B) Some drip irrigation systems are not completely maintenance-free.
(C) No drip irrigation system is automated.
(D) All automated systems are drip irrigation systems.
Answer Key:
B
Step-by-Step Solution & Explanation
From Statement 1 ("Some Drip are Automated") and Statement 2 ("All Automated require Sensors"), it follows that "Some Drip require Sensors". Combining this with Statement 3 ("No Sensor device is Maintenance-free"), the subset of drip irrigation systems that use sensors cannot be maintenance-free. Therefore, "Some drip irrigation systems are not completely maintenance-free."