The effects of technology on language and the effects of language on culture as a whole are profound and complex.
Statements
causal (the effects are profound / complex)
Technology ⇢ language ⇢ culture
causal (X changed Y, in turn made Z)
telegraph, changed the way telephone, ⇢ people speak to television one another
loosening of relationships Email ⇢ language usage ⇢ between people rules more casual
Evaluate / Goal
The correct answer on Proposition / Generalization questions is usually a very safely worded takeaway that summarize or reinforces the Causal relationship identified in the passage.
In this case, the statements emphasized the impact of technology (such as email) on language (loosening of the rules), and the effect of language on culture (relationships are more casual).
There is a causal chain from Technology to Culture / Interpersonal Relationships, so the answer may reward us for seeing that A ⇢ B ⇢ C connection.