I did it - I completed my long , long walk along the Thames Path ! It was really tough and there was more than one moment yesterday afternoon when I was seriously considering if I could get away with catching the bus but I made it all the way to the Thames Barrier . The excitment of it being the last day really got me going in the morning and I was whizzing along but it did n't last and by the time the sun was high in the sky I was too hot and too tierd and really struggling .

Generate a question about the above context.
Why would the writer complete a long walk along Thames path ?
Choices:
(a). None of the above choices .;
(b). Because they made it all the way to Thames barrier .;
(c). Because the sun was high in the sky .;
(d). Because they wanted to challenge themselves .;