on plato i got this wrong, so i looked into and worked on it, i figured it out!
"Barthelemy Thimonnier, a French tailor, invented a wooden chain stitch machine."
therefore it should be, b. the wooden chain!
What's ur problem? That's just a title
I think that the people hidden in the elderly couple's faces is them when they were young, and that may be how they met. I think it shows that they grew old together.