How to remove indentation when using the aligned environment? [duplicate]

I want to align equations inside an enumeration, so I use the aligned environment and its [t] option to make the first equation appear on the same baseline as the item label:

\documentclass{article}
\usepackage{amsmath, enumitem}

\begin{document}
\begin{enumerate}[align=left, leftmargin=*, label=\large\sffamily\bfseries \alph*)]
\item $a = 1$
\item
\begin{aligned}[t] a &= 1\\ b &= 2\\ c &= 3 \end{aligned}
\end{enumerate}
\end{document}


This works quite well, but I noticed that the aligned environment introduces a small indentation (I added the red line for better visualization):

How can this be solved? Or is there an even better alternative to aligned?