You need a quick answer from your father about a type of beef he asked you to pick up from the store. a quick exchange of this type could benefit from:

Modern electronic communications enables this situation to be handle quickly and efficiently through the use of SMS or text messages. The information needed to exchanged would require only a very small amount of actual communication. 

You the sender could write: "What kind of beef?" and "How much?" Your father's response of one or two words would finish the exchange, unless your father requested something else.

The efficiency, how easy and effectively something can be used, addresses along with the speed of the message by being only a short number of characters. In addition, either predictive text, which could quickly finish off the first three words and most likely the forth of "beef" after the "b" and "e" are presses, would be about as fast as you could do it.

Of course there could be some problems with your father if he is not very good with technology, or has trouble texting in general. As such an alternative could be to just use the phone. Although this would require more energy and thus be less efficient, it would still effectively help to complete the task. If your father sends back a garbled or unclear message, you would have to call anyways, so it is at your discretion - what you think, as to how you would communication your need for additional information to complete the task.