Answer:
The answer is: A pithy slogan.
Step-by-step explanation:
Let's discard the other options first...
We have: alliteration, and in this slogan it is not used this technique as this term refers to sames sounds or same consonants at the beginning of each word -this is not the case. A word play is mostly known for creating contradictions and/or redundancies -again, this is not the case. And finally a pithy phrase or slogan accordind to this context, means to give a brief but full of meaning phrase, needless to include so many words to let your audience know what you exactly mean, which here, it is the case:
- The window cleaner that makes glass invisible again.
What else could we add? Nothing as it is clear that if you use that product, your windows will be super clean!